FIELD OF THE INVENTION
The present invention refers to skates with aligned wheels, that is to say those skates widely used nowadays and also known by the English naming "in-line" skates.
As is known, these skates consist basically of a frame supporting the wheels according to the particular in-line arrangement mentioned above, and a boot fitted onto such frame.
Considering the current prevailing commercial trends, it is possible to divide the aforesaid skates on the basis of the type of boot mounted on the frame; in particular it is possible to distinguish two distinct categories of skates: those with rigid boots and those with soft boots.
In the first of said classes the boot consists of a rigid shell, generally made from plastic material, which includes a sole that represents the part of the boot fixed to the frame; on the shell there is hinged, with bosses or pins, a leg portion which defines the upper part of the boot.
Also the leg portion is made from plastic material like that of the shell and together with the latter they enclose a padded inner shoe, in which the skater's foot is comfortably accomodated. In order to assist the ventilation of the foot it is also known to provide in the shell and/or the leg portion, openings that allow the passage of air.
In the second class of skates instead of the rigid shell described above there is a shoe with a flexible upper made preferably from synthetic fabric; the shoe is fixed by means of adhesive or other suitable systems to a rigid support or abutment which is located in the region of the heel, as well as to a toe-piece also rigid located at the tip: both the abutment and the toe piece are solid with a sole fitted onto the frame.
The abutment of these skates extends up to the level of the malleoli and a rigid leg portion of the type used for the rigid boots already mentioned above, is hinged on it; however, differing from what occurs in the other type of skates, the flexible upper per se allows a good transpiration and ventilation of the foot and there is therefore no need to arrange specific openings on it for this purpose.
Examples of skates produced according to this last teaching are known from International Patent Application No. PCT/FR96/01618 in the name of Salomon, and from European Patent Application No. 0 780 062 in the name of Nordica, both already published. In practice the principal difference between the respective skates to which these two applications refer, lies in the fact that in the first one the flexible upper finishes slightly above the hinging points of the rigid leg portion, which therefore has its own independent inner padding, whereas in the second one the flexible upper extends up to the calf (the inner shoe is therefore similar to an ankle-boot) so that a rigid leg portion hinged to the abutment can be fitted externally thereof.
In general it may be stated that the rigid boots provide greater immediacy in the control transmission from the foot to the skate, while the soft boots offer greater comfort; consequently the former are more suitable for skates in which greater manoeuvrability is required, whereas the latter are more suitable where a higher degree of comfort is preferred.
There are however situations in which neither type of skates is capable of satisfactorily obtaining the performances demanded of them.
For example there are cases wherein the skater makes large movements, such as during long duration competition, in the course thereof the legs of the athlete describe a wide stride for which the ankle must be able to be bent in an accentuated manner; on such occasions neither the skates with rigid boots nor those with soft boots can provide adequate freedom of movement for the ankle and ensure in the meantime the necessary effect of containing and supporting the foot for correct skating.
In both cases indeed the rigid leg portion inevitably limits the flexing of the ankle, since it fits closely round the bottom of the leg with respect to which, in its rotations about the hinging pins, it assumes positions that increasingly diverge as the inclination of the ankle increases.
Such divergence causes interference and friction between the skater's leg and the leg portion of the boot, which cannot be tolerated for prolonged periods, as in the case of the long duration competitions mentioned above, since they cause painful stresses in the athletes and limit their performances.